


Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
874 ACUS02 KWNS 081718 SWODY2 SPC AC 081717 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1217 PM CDT Tue Jul 08 2025 Valid 091200Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE EAST AND THE NORTHERN PLAINS... ...SUMMARY... Scattered damaging winds are possible on Wednesday afternoon to early evening from the Carolina Piedmont towards the Delaware Valley. Isolated significant severe hail and sporadic severe gusts are also possible across parts of the Dakotas from late afternoon to mid-evening. ...Southeast to Mid-Atlantic States... A lower-amplitude mid-level trough should drift east across the central to Lower Great Lakes and OH Valley, north of a mid-level anticyclone over the northeast Gulf. A belt of moderate mid-level southwesterlies will be centered on the Mid-Atlantic, diminishing with southward extent in the Southeast. Scattered to widespread thunderstorms are expected to develop during the afternoon over the southern Appalachians and Blue Ridge Mountains, spreading across the adjacent Piedmont. Rather rich boundary-layer moisture downstream will compensate for weak mid-level lapse rates to support an extensive plume of MLCAPE from 2000-3000 J/kg. A few semi-organized clusters may develop from VA towards DE Bay owing to the more favorable shear. However, water-loaded downbursts producing damaging winds appear to be the overarching scenario, which is signaled by the 12Z HREF max wind speed field. ...Northern Great Plains... Just downstream of a low-amplitude mid-level ridge emanating north from an anticyclone over the Southwest, guidance suggests that isolated to scattered late-afternoon thunderstorms should form along a weak surface trough. Low-level moisture ahead of this trough will gradually build beneath a stout EML. A corridor of large to extreme buoyancy is probable from a portion of western/central ND into NE by peak heating. Despite modest mid-level west-northwesterlies owing to the ridge proximity, stronger upper-level westerlies will support adequate deep-layer shear for a few supercells. Significant severe hail will be possible in any sustained supercells. Outflow-dominated downdrafts should foster clustering east-southeastward with a risk for sporadic severe gusts before waning Wednesday night. ...Interior Northwest... Downstream of a shortwave trough moving east across northern CA into the northwest Great Basin, an elongated belt of moderate mid-level southwesterlies will exist into MT. Within this favorable flow regime, scattered afternoon to early evening thunderstorms will aid in strong to isolated severe gusts from eastern OR to southern/central/eastern MT. ...Lower MI... Isolated, marginally severe hail and locally damaging winds are possible as scattered thunderstorms develop during the afternoon, supported by a modest combination of deep-layer shear/buoyancy. ..Grams.. 07/08/2025 $$